CoI points to 'human error' for Su-30MKI crash; Minor design modifications sought

[Screaming Skull]

IAF taking steps to prevent another SU-30MKI crash​

Saturday, Jun 27, 2009

• Crash in April resulted in the entire fleet being grounded
  
• Aircraft needs to be better covered to prevent heat soak due to exposure to sun
  
• There are calls for design change including wire-locking the switches in cockpit

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BANGALORE: The Indian Air Force is initiating steps aimed at preventing another SU-30MKI crash like the one that occurred near Jaisalmer in April during a routine air exercise, killing the co-pilot and destroying a Rs. 200-crore fighter aircraft.

Highly placed sources in the Ministry of Defence told The Hindu that a joint probe by Indian and Russian Defence and flight engineers zeroed-in on the causes for the crash and suggested remedial action.

While one step will involve better covering of the aircraft when they are parked on the tarmac under to prevent heat soak, the other calls for design change, including wire-locking the switches in the cockpit that control power supply to the aircraft’s flight control computer.

The crash of the long range, high endurance SU-30MKI, the Indian Air Force’s most modern and lethal fighter, sent both the IAF and the aircraft designers, Russia’s Sukhoi Design Bureau, into a tizzy given the fighter’s exceptional and unrivalled flight safety record. The crash also forced the IAF to ground its entire Sukhoi fleet temporarily, compromising the country’s airpower.

The Court of Inquiry (CoI) that went into the crash found that the pilot, Wing Commander S. V. Munje, inadvertently switched-off the four switches that control the power supply to the computer. Switching-off the power not only cuts off the power supply to the computer, but is also irreversible. Switching them on does not ‘power on’ the all important unit.

The aircraft went into a forward bunt, lost control and crashed, killing Wing Commander P. S. Nara, an officer from the IAF’s Directorate of Air Staff Inspection (DASI).

During the flight, the aircraft is said to have experienced a technical glitch after a round of firing practice. The pilot, who was also under routine inspection by the DASI, is said to have then tried to switch-off the armament master switches, which are located just behind the pilot’s seat and in close proximity to the switches that control power to the flight control computer.

Though the CoI’s conclusion was that the crash occurred due to pilot error, a number of officials are questioning the placing of critical switches that are not to be used during in flight and only for power on when the aircraft is on theground in the cockpit and also, the inadequate in-built safety mechanisms like a wire lock or even a covering flap.

Said a former SU-30MKI pilot: “It is unpardonable and a poor design to have such critical switches, which are not to be used by the pilot in such an accessible manner. The Air Force should insist on design changes.”

The probe also revealed that the ejection seat’s harness had broken, leading to the death of Wing Commander Nara.

The reason for the breaking is being attributed to material failure of the harness due to exposure to the sun. The IAF has taken steps to have the aircraft more adequately covered.

The Hindu : National : IAF taking steps to prevent another SU-30MKI crash